Substrate processing systems, such as plasma reactors, may be used to deposit, etch, or form layers on a substrate or otherwise treat surfaces of the substrate. One technique useful for controlling aspects of such substrate processing is use of radio frequency (RF) energy to control a plasma proximate the substrate, such as by coupling RF energy to an electrode disposed beneath a substrate disposed on a substrate support.
The inventors provide herein embodiments of substrate processing systems that may provide improved RF energy control of the substrate processing system, and flexible control of plasma sheath at the vicinity of the wafer edge.